1. Field of the Invention
This invention relates, generally, to coin operated mechanisms and, more particularly, to a control device for preventing the inadvertent or unauthorized initiation of the operating cycle of said mechanism.
2. Description of the Prior Art
Coin operated mechanisms of the type commonly referred to as commercial appliances, such as, clothes washers and dryers, are usually provided with rotary coin meters or coin slide assemblies which require the insertion of one or more coins to initiate the operating cycle of the mechaism. The length or duration of the operating cycle is controlled by an electrically operated timer which is part of the control device. Examples of such prior art control devices are disclosed in U.S. Pat. Nos. 2,915,692; 3,168,947; 3,172,520 and 3,614,681.
In one form of such control device, a ratchet wheel and a star wheel are rotatably mounted on a common shaft. Each of said wheels carries an eccentrically mounted pin located at an equal radial distance from the axis of the shaft. The pins project toward one another and are adapted to engage upon rotation of one wheel relative to the other. The ratchet wheel is driven or stepped by a pawl assembly which, in turn, is operatively associated with either a coin slide assembly or solenoid assembly. In either case, deposit of a proper coin in the device permits the coin slide or solenoid to operatively move the pawl assembly in a manner to stepwise rotate the ratchet wheel in one direction a distance of one tooth. Such rotation establishes an angular separation between the pins of the ratchet wheel and the star wheel. A spring biased arm is provided which operatively connects the rachet wheel to a switch. The operation is such that rotation of the ratchet wheel effects movement of the arm to a position which, in turn, effects movement of the switch to a closed state to initiate the operating cycle of the mechanism.
Movement of the switch to its closed state also serves to energize an electrically operated timer which, in turn, effects rotation of a pin wheel attached to the timing motor shaft. Rotation of the pin wheel causes the pins thereof to engage with the teeth of the star wheel and intermittently rotate said star wheel in the same direction of rotation of the ratchet wheel. Rotation of the star wheel causes the pin thereof to engage with the pin of the ratchet wheel. Continued rotation of the pin wheel effects conjoint rotation of the star wheel and the ratchet wheel in said one direction, dur to the engagement of said pins, and serves to displace the switch operating arm to a position to effect movement of the switch to its open state to de-energize the timer and terminate the operating cycle of the mechanism.
In the device as described above, it is possible for the star wheel to counterrotate in a direction opposite to said one direction when the switch is in its open state. Such counterrotation of the star wheel permits the ratchet wheel to similarly counterrotate in said opposite direction under the influence of the spring biased switch arm. However, the counterrotation of the ratchet wheel due to the movement of the switch arm also effects movement of the switch to its closed state to thereby inadvertently initiate the operating cycle of the mechanism. Thus, the mechanism may be subjected to unauthorized use without first depositing the proper coin or coins in the control device.
The extent to which the star wheel can counterrotate is a function of the rotational play of said wheel and the rotational play of the timer pin wheel. However, it only takes a slight degree of rotational play to inadvertently initiate the operating cycle of the mechanism. In practice, it has been found that a slight jar of the control device was all that was necessary to initiate the operating cycle. In other instances, the mere force being exerted by the spring biased switch arm on the ratchet wheel was sufficient to effect the degree of counterrotation necessary of said ratchet wheel and said star wheel to initiate said operating cycle.
Heretofore, restraining means have been proposed to prevent the inadvertent initiation of the operating cycle of the mechanism. For example, in U.S. Pat. No. 2,915,692, the means for stepping the ratchet wheel comprised an oscillatably mounted spring biased operating arm having a spring wire that was positioned to slip over one tooth of the wheel upon advanced movement of said arm. The movement of the operating arm was effected by the projected movement of the coin slide to its operate position. The arrangement was such that, upon retracted movement of the coin slide, the arm returned to its original position which, in turn, caused the bent end of the wire to rotate the ratchet wheel by a distance of one tooth.
In order to prevent forceful turning of the timer control knob with the resulting damage to the spring wire, a bracket was provided having a portion overlying the surface of the teeth of the ratchet wheel. The bracket was positioned such that, in the spring retracted position of the operating arm, the bracket engaged the bent wire end and reinforced it in a manner to block or prevent counterrotation of the ratchet wheel. While such restraining means proved satisfactory for the specific structure disclosed in said patent, the arrangement is not suitable for newer control devices incorporating different means for stepping the ratchet wheel. The present invention provides improved restraining means, as hereinafter disclosed, to prevent the counterrotation of the star wheel and the ratchet wheel when the switch is in its open state.